Measurement of porosity and specific surface area of coal rock using CT images

Jin Zhimin●Zhou Hongwei●Xue Dongjie

Abstract

In order to realize the rapid measurement of porosity and specific surface area of coal using CT images, a measurement method based on MATLAB image processing is proposed. Taking the coal rock obtained from the deep part of Pingdingshan Coal Mine Group 12 as the research object, the sample was scanned by Nano-CT, and the porosity and specific surface area were calculated by Avizo and MATLAB software respectively. The advantages and disadvantages of Avizo 3D modeling and MATLAB image processing were studied. It is pointed that the errors calculated by the two methods are only about 10%,with the error done by the composite Cotes formula the smallest. The errors of porosity and specific surface area are 9.392% and 8.247%,respectively.The results indicate that the traditional measurement method based on Avizo 3D modeling is more accurate, and the 3D pore network model and the shape, orientation and size distribution of pores can be obtained. However, the calculating process is comparatively complicated, and it is necessary to perform multiple calculations for a plurality of samples, with high quality requirements for CT images. The measurement method based on MATLAB image processing proposed in this paper realizes the rapid calculation of porosity and specific surface area of coal by simple numerical integration, which avoids 3D modeling, reduces the computational complexity greatly, and processes multiples at a time. The sample satisfies the engineering needs well. Moreover, for CT images, there is a higher fault tolerance rate, and only a few CT images with better scanning quality effects are needed for each calculation.

引用格式：

Jin Zhimin, Zhou Hongwei, Xue Dongjie. Measurement of porosity and specific surface area of coal rock using CT images [J], Xi’an University of Science and Technology, 2020, 40(01):133-140.

文章链接地址：

http://xkxb.xust.edu.cn/oa/darticle.aspx?type=view&id=202001018